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Reply to "Carb sync-ing"

Guys thanks for the feedback. 

Danny l used the washers purely to hold the revs, in this instance @ 2500rpm. I did not want to connect any linkage until they are reading the same or similar.   If l can't get them reading without the linkage then no point hooking everything else up.

I've been doing some digging on the web regarding the air bleed screws. A lot of question with uncertain answers but nothing concrete. 

Decided to call a carb importer and parts supplier here in the U.K.. after a indepth chat etc he advised not to adjust the airbleed screws to sync the 2 carbs. He did advise to swap the carbs over and see if the problem persisted on the same side or if it had swapped sides. Indicating a carb or an engine problem depending on results.

So this afternoon l got my tools out and pulled both carbs. Took the opportunity to give them a quick blast with carb cleaner, not that they were dirty. Upon doing this l noticed the length of the air bleed screws protruding from the locknuts was different from carb to carb. I cracked open the lock nuts on one carb and found that one screw was 2 turns out and the other on the same carb was 1 1/2 turns. Proceeding onto the other carb, both locknuts cracked, l found that both air bleed screws were in the fully closed position.  Interesting...as l never touched them...

So decided not to swap carbs from one side to the other at this moment, instead l adjusted all the air bleed screws so that they were all 1 1/2 turns out as a starting point. I've now put the carbs back as they were without any linkage connected and got the engine started and warmed up. Running lumpy but once warm and l re synced the carbs at idle again things smoothed out as before. now for the part throttle bit. Decided to sacrifice a feeler gauge to be 100% cut in half trapped between the idle screw and throttle stop arm as before to pick up and hold the revs. 

Surprisingly both carbs with the Snail read the same reading of 13 on the Snail. Pulled  the feeler gauges out and they returned to idle reading the same 5.5 in the Snail. It's a great feeling making progress and finally getting to the bottom of something.

Just need to take it for a run and see how it goes. Not sure how much the air bleed screws should be turned out or in. Alot have mentioned about flat spots if out or in to much so trail and error guess at this stage.

 

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